The subject of the present invention is an automatic machine for preparing espresso coffee from coffee beans, particularly for domestic use.
The machine of the invention is of the type comprising essentially:
a motor-driven coffee grinder with a container for receiving a supply of coffee beans; PA1 a source of pressurised hot water; PA1 a percolation chamber connected by a supply duct to the output of the coffee grinder to receive a charge of ground coffee, and having means for closing the chamber and compressing the charge, means for expelling the coffee grounds, a port for the inlet of hot water from the source, and an outlet spout for the drink of coffee, and PA1 programmed means for controlling a cycle comprising, in succession, the grinding of the coffee and its supply to the percolation chamber, closure of the chamber and compression of the charge, percolation, and the expulsion of the exhausted coffee grounds.
Machines of this type are already known in which the ground coffee passes through the supply duct from the coffee grinder to the percolation chamber under gravity. A disadvantage of such machines is the fact that the duct frequently becomes blocked since the ground coffee, being rather thick, does not slide easily and cannot flow at the same rate as that at which it is supplied by the coffee grinder.